When do you.....

Lineslinger · Oct 31, 2019

Re - torque the head.
212 miles on rebuilt engine, I re-torqued the head while still hot/warm.
No leaks, no issues.
How many more miles would you put on it before round 2?

Nortoniggy · Oct 31, 2019

I wouldn't do it again.

Fast Eddie · Oct 31, 2019

If it’s a composite gasket I would do it a couple more times.

It is amazing how much a composite gasket compresses, and when it does, it effectively loosens the head fasteners.

And I’d do it again straight away, as it should be done COLD.

FWIW I’ve used a composite gasket a few times now on my 850 and have never had any leaks or weeps at all. I’m using a copper gasket for the first time as I’m now running a 920 motor, it’s not leaking anywhere yet... but I don’t have the same confidence it’ll stay that way...!

Onder · Oct 31, 2019

I thought the same thing. When cold it shrinks. Make sure it is over night cold before you have at it.

ashman · Oct 31, 2019

Depends on what head gasket you fit, I run copper head gaskets on all my rebuilds now and only retorque at 500 miles and no more, with composite they need a few more times, I have had a few problems with composite gaskets with leaks and no longer use them, well that was a very long time ago when I had problems and retorque when cold never hot.

Ashley

Danno · Oct 31, 2019

If you check it and some bolts/nuts need tightening, check it again and again until it holds torque. I checked the Titanic's head (composite gasket) and no additional tightening was required. Might check it again for shits and giggles.

Danno · Oct 31, 2019

Just as a general survey, what fasteners tend to get loose? I used 5 new bolts on the Titanic and all the old studs/nuts. I would think the new bolts would be more likely to loosen than nuts on studs when the studs haven't been disturbed.

marshg246 · Oct 31, 2019

I have no experience with composite gaskets so I can't say about them - I only use properly annealed copper gaskets.

On Triumph and BSA, I've never retorqued a head. On Norton, I retighten once with a cold engine and never again unless I see a problem. It's difficult to use a torque wrench on some of the Norton head fasteners and since they are different sizes, very difficult to get the clamping force even.

When I build an engine, I make sure that every nut, bolt, and stud smoothly threads - this helps to get the torque/tightness right.

Fast Eddie · Oct 31, 2019

Danno said:
Just as a general survey, what fasteners tend to get loose? I used 5 new bolts on the Titanic and all the old studs/nuts. I would think the new bolts would be more likely to loosen than nuts on studs when the studs haven't been disturbed.

It’s not really anything to do with new vs old fasteners, it’s not the fasteners stretching that causes the loss of torque (unless someone’s using plasticine fasteners) it’s the gasket compressing that causes it.

Which means that all fasteners should be checked.

ashman · Oct 31, 2019

I am still using all my orginal head bolts and studs, but have replaced a few nuts that were slightly rounded from using the wrong size spanners before I got myself a full set of WW ring, open enders and sockets, all the years I have done work on my Norton without any WW tools, make it a lot easier using the right tools, in my younger days I used what I had.
In 43 years I have only had one head bolt that came loose.

Ashley

texasSlick · Oct 31, 2019

Danno said:
If you check it and some bolts/nuts need tightening, check it again and again until it holds torque.

Plus 1

Slick

texasSlick · Oct 31, 2019

Fast Eddie said:
It’s not really anything to do with new vs old fasteners, it’s not the fasteners stretching that causes the loss of torque (unless someone’s using plasticine fasteners) it’s the gasket compressing that causes it.

Which means that all fasteners should be checked.

Plus one

Slick

JimC · Oct 31, 2019

Bear in mind with all fasteners it’s tension that is the critical factor. Torque is only a relative indicator of the tension being applied. Torque readings can be grossly affected by anything that resists rotational force.

Lineslinger · Oct 31, 2019

Good stuff.
I used a Victor Reinz composite. I also replaced the old studs and nuts with ARP fasteners during overhaul.

I know I can find a thread on composite vs. copper or aluminum head gasket somewhere in here but I'm too lazy to dig around. In a nutshell what are the advantages (if any) of metal over composite head gasket.
Thanks for the feedback.

NickZ · Oct 31, 2019

When re-torqueing head fasteners, is it proper technique to loosen first then tighten to torque spec, or just tighten?

seattle##gs · Oct 31, 2019

marshg246 said:
I have no experience with composite gaskets so I can't say about them - I only use properly annealed copper gaskets.

On Triumph and BSA, I've never retorqued a head. On Norton, I retighten once with a cold engine and never again unless I see a problem. It's difficult to use a torque wrench on some of the Norton head fasteners and since they are different sizes, very difficult to get the clamping force even.

When I build an engine, I make sure that every nut, bolt, and stud smoothly threads - this helps to get the torque/tightness right.

With Triumphs I usually retorque at least 8 times trying to keep the head on and no leaks. The bolts are only tightened 18 and 16 ft/lbs and back off with each ride. I use the composite gasket, surfaced head and cylinder and don't bother installing the head steady untill the head settles down. Even with waisted studs it loosens up at least 8 times.

Fast Eddie · Oct 31, 2019

Lineslinger said:
Good stuff.
I used a Victor Reinz composite. I also replaced the old studs and nuts with ARP fasteners during overhaul.

I know I can find a thread on composite vs. copper or aluminum head gasket somewhere in here but I'm too lazy to dig around. In a nutshell what are the advantages (if any) of metal over composite head gasket.
Thanks for the feedback.

Copper is a great head gasket material. I’ve used copper on Triumph, Nourish, etc, for years without issue.
One big advantage of copper is that if the gasket does start to go, it’ll blow a bit but still function for quite a while, whereas if a composite gasket starts to go, it takes less time until it blows out completely.

However, on a Norton the head gasket has to do more work than on a Triumph, it has to seal around the oil drain hole and, even more tricky, around the pushrod tunnels.

Composite gaskets have sealed with 100% success for me so I’ve really come to like using them on Norton’s. Copper gaskets have a big reputation for oil leaks / weeps on Norton’s.

marshg246 · Oct 31, 2019

seattle##gs said:
With Triumphs I usually retorque at least 8 times trying to keep the head on and no leaks. The bolts are only tightened 18 and 16 ft/lbs and back off with each ride. I use the composite gasket, surfaced head and cylinder and don't bother installing the head steady untill the head settles down. Even with waisted studs it loosens up at least 8 times.

Good reason to switch to copper!

comnoz · Oct 31, 2019

I don't run any head gasket, solid metal to metal, but I still find it is necessary to retorque the head bolts 3 or 4 times before they stop getting loose.

kerinorton · Oct 31, 2019

I have used the same copper gasket I got with the bike. I don't anneal it. I basically wet both sides with a tiny amount of silicon, fit the gasket the same way up, and fit the head quick. I torque it up once then just ride it and don't have any issues and no oil leaks.

I see no one is poo hooing Jim C's method yet. No risk of blowing gaskets that way. Jim probably has more advanced ways of making sure both surfaces mate together than most of us.

When do you.....

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